1. Field of the Invention
The present disclosure generally relates to a device management apparatus and method for managing one or a plurality of network devices which are connected via a network and more particularly to a device management apparatus and method for controlling transmission of the device information by the network devices using a trap processing.
2. Description of the Related Art
In recent years, various network devices, such as image processing devices, are introduced in office environments. There is a request for a system administrator to supervise the states of the network devices and efficiently manage the network devices. For this purpose, a device management system which manages a plurality of network devices which are connected via a network, in a unified manner has been introduced in office environments.
When there are many network devices that are management objects in the office environments, an important issue of the device management system is how to supervise the states of the network devices in the network, or a method of acquiring device information of the network devices.
For example, Japanese Laid-Open Patent Publication No. 2003-296206 discloses a system for managing network devices wherein trap processing and polling processing are properly used as a method of acquiring the device information from the network devices in SNMP (simple network management protocol). The trap processing is a process which is used to dynamically report device information of a network device to a management station when a change of the state of the network device is detected. Even if an information acquisition request from the management station is not transmitted to the network device, the management station is able to acquire the device information from the network device.
On the other hand, the polling processing is a process which is used to periodically transmit an information acquisition request from the management station to each of the network devices, and accordingly the management station acquires the device information from each network device.
However, in the method of acquiring the device information using the trap processing according to the related art, even after a network device is excepted from the management objects, the trap setting of the excepted device remains unchanged (or the trap setting being kept in an ON state). Hence, the device information from the excepted device will be transmitted to the management station, and there is a problem that the communication load is unnecessarily increased.
It is difficult for the device information acquiring method according to the related art to change the trap setting of an excepted network device to an OFF state (or cancels the trap setting) in accordance with a change of the state of the network device. Hence, it is difficult for the device information acquiring method according to the related art to avoid the useless communication between the management station and the network device in the device management system.